Battery life / replacement

[Steve B]

my Boxster is now over 5 years old and doing well I still have the original battery and was thinking of replacing it before it fails. Car is driven most days, but not all and kept in a garage.

Any thoughts on the subject? Where would you buy a replacement battery?

[ar38070]

As long as you have a way to jump the car if it does not start then I would wait till it fails. Usually when the battery gets weak you will notice that after the car sits for a few days the car will barely start or not start at all. That is usually the sign that it is time to replace the battery. I have one of those portable battery jumpers that you can usually get for $30 at Target, one of the auto parts stores or Costco.

Here is some info about battery sizes that I got off of the web:
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The three group sizes that fit Boxsters and 996 (and maybe 964 and 993 type 911s)
are 90, 91 and 92, with size 90 being the smallest and each higher number 1.25 inches
longer than the previous. Group size 90 was not delivered on U.S. Boxsters and is not
in the U.S. parts system. My 1999 996 (no longer owned) and 2003 Boxster S were
delivered with size 92.

U.S. suppliers often substitute group size 48 for these cars, but it turns out that
group size 47 (a shorter version of size 48) matches the length and width of size 90
exactly and has the same mounting projections on the base. The height is slightly
different but does not pose a problem.

The factory delivered size 92 battery in my Boxster S weighs 46.5 lbs as does an
Exide replacement of the same size at a local race shop. Size 47 at Sears weighs
30 pounds, so the weight savings is slightly less than I previously stated.
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I also have a doc that shows how to mount an optima battery if you want to go that route. I can email it to you if you want.

[CatalogGuy]

At right about 4 years mine quit. Bought a new one from Pep Boys for about $80.

Originally Posted by Steve B

my Boxster is now over 5 years old and doing well I still have the original battery and was thinking of replacing it before it fails. Car is driven most days, but not all and kept in a garage.

Any thoughts on the subject? Where would you buy a replacement battery?

[Steve B]

Thanks ar38070 for the quality of your response. It was very helpful.

Thanks Tom, the "similar threads" feature was also helpful. I'm liking the system more.

Thanks Andrew, but I thought you would have bought somrthing from the miltary for use with tanks based upon previous battery questions

I will probably go to Sears. It's about time for a new battery and Sears has worked for me in the past.